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Diffstat (limited to 'arch/x86/kernel/cpu/perf_event_p4.c')
-rw-r--r--arch/x86/kernel/cpu/perf_event_p4.c74
1 files changed, 59 insertions, 15 deletions
diff --git a/arch/x86/kernel/cpu/perf_event_p4.c b/arch/x86/kernel/cpu/perf_event_p4.c
index ef484d9d0a2..5d466b7d860 100644
--- a/arch/x86/kernel/cpu/perf_event_p4.c
+++ b/arch/x86/kernel/cpu/perf_event_p4.c
@@ -895,8 +895,8 @@ static void p4_pmu_disable_pebs(void)
* So at moment let leave metrics turned on forever -- it's
* ok for now but need to be revisited!
*
- * (void)checking_wrmsrl(MSR_IA32_PEBS_ENABLE, (u64)0);
- * (void)checking_wrmsrl(MSR_P4_PEBS_MATRIX_VERT, (u64)0);
+ * (void)wrmsrl_safe(MSR_IA32_PEBS_ENABLE, 0);
+ * (void)wrmsrl_safe(MSR_P4_PEBS_MATRIX_VERT, 0);
*/
}
@@ -909,9 +909,8 @@ static inline void p4_pmu_disable_event(struct perf_event *event)
* state we need to clear P4_CCCR_OVF, otherwise interrupt get
* asserted again and again
*/
- (void)checking_wrmsrl(hwc->config_base,
- (u64)(p4_config_unpack_cccr(hwc->config)) &
- ~P4_CCCR_ENABLE & ~P4_CCCR_OVF & ~P4_CCCR_RESERVED);
+ (void)wrmsrl_safe(hwc->config_base,
+ p4_config_unpack_cccr(hwc->config) & ~P4_CCCR_ENABLE & ~P4_CCCR_OVF & ~P4_CCCR_RESERVED);
}
static void p4_pmu_disable_all(void)
@@ -943,8 +942,8 @@ static void p4_pmu_enable_pebs(u64 config)
bind = &p4_pebs_bind_map[idx];
- (void)checking_wrmsrl(MSR_IA32_PEBS_ENABLE, (u64)bind->metric_pebs);
- (void)checking_wrmsrl(MSR_P4_PEBS_MATRIX_VERT, (u64)bind->metric_vert);
+ (void)wrmsrl_safe(MSR_IA32_PEBS_ENABLE, (u64)bind->metric_pebs);
+ (void)wrmsrl_safe(MSR_P4_PEBS_MATRIX_VERT, (u64)bind->metric_vert);
}
static void p4_pmu_enable_event(struct perf_event *event)
@@ -957,7 +956,7 @@ static void p4_pmu_enable_event(struct perf_event *event)
u64 escr_addr, cccr;
bind = &p4_event_bind_map[idx];
- escr_addr = (u64)bind->escr_msr[thread];
+ escr_addr = bind->escr_msr[thread];
/*
* - we dont support cascaded counters yet
@@ -978,8 +977,8 @@ static void p4_pmu_enable_event(struct perf_event *event)
*/
p4_pmu_enable_pebs(hwc->config);
- (void)checking_wrmsrl(escr_addr, escr_conf);
- (void)checking_wrmsrl(hwc->config_base,
+ (void)wrmsrl_safe(escr_addr, escr_conf);
+ (void)wrmsrl_safe(hwc->config_base,
(cccr & ~P4_CCCR_RESERVED) | P4_CCCR_ENABLE);
}
@@ -1005,8 +1004,6 @@ static int p4_pmu_handle_irq(struct pt_regs *regs)
int idx, handled = 0;
u64 val;
- perf_sample_data_init(&data, 0);
-
cpuc = &__get_cpu_var(cpu_hw_events);
for (idx = 0; idx < x86_pmu.num_counters; idx++) {
@@ -1034,10 +1031,12 @@ static int p4_pmu_handle_irq(struct pt_regs *regs)
handled += overflow;
/* event overflow for sure */
- data.period = event->hw.last_period;
+ perf_sample_data_init(&data, 0, hwc->last_period);
if (!x86_perf_event_set_period(event))
continue;
+
+
if (perf_event_overflow(event, &data, regs))
x86_pmu_stop(event, 0);
}
@@ -1258,7 +1257,24 @@ again:
pass++;
goto again;
}
-
+ /*
+ * Perf does test runs to see if a whole group can be assigned
+ * together succesfully. There can be multiple rounds of this.
+ * Unfortunately, p4_pmu_swap_config_ts touches the hwc->config
+ * bits, such that the next round of group assignments will
+ * cause the above p4_should_swap_ts to pass instead of fail.
+ * This leads to counters exclusive to thread0 being used by
+ * thread1.
+ *
+ * Solve this with a cheap hack, reset the idx back to -1 to
+ * force a new lookup (p4_next_cntr) to get the right counter
+ * for the right thread.
+ *
+ * This probably doesn't comply with the general spirit of how
+ * perf wants to work, but P4 is special. :-(
+ */
+ if (p4_should_swap_ts(hwc->config, cpu))
+ hwc->idx = -1;
p4_pmu_swap_config_ts(hwc, cpu);
if (assign)
assign[i] = cntr_idx;
@@ -1271,6 +1287,17 @@ done:
return num ? -EINVAL : 0;
}
+PMU_FORMAT_ATTR(cccr, "config:0-31" );
+PMU_FORMAT_ATTR(escr, "config:32-62");
+PMU_FORMAT_ATTR(ht, "config:63" );
+
+static struct attribute *intel_p4_formats_attr[] = {
+ &format_attr_cccr.attr,
+ &format_attr_escr.attr,
+ &format_attr_ht.attr,
+ NULL,
+};
+
static __initconst const struct x86_pmu p4_pmu = {
.name = "Netburst P4/Xeon",
.handle_irq = p4_pmu_handle_irq,
@@ -1305,14 +1332,17 @@ static __initconst const struct x86_pmu p4_pmu = {
* the former idea is taken from OProfile code
*/
.perfctr_second_write = 1,
+
+ .format_attrs = intel_p4_formats_attr,
};
__init int p4_pmu_init(void)
{
unsigned int low, high;
+ int i, reg;
/* If we get stripped -- indexing fails */
- BUILD_BUG_ON(ARCH_P4_MAX_CCCR > X86_PMC_MAX_GENERIC);
+ BUILD_BUG_ON(ARCH_P4_MAX_CCCR > INTEL_PMC_MAX_GENERIC);
rdmsr(MSR_IA32_MISC_ENABLE, low, high);
if (!(low & (1 << 7))) {
@@ -1328,5 +1358,19 @@ __init int p4_pmu_init(void)
x86_pmu = p4_pmu;
+ /*
+ * Even though the counters are configured to interrupt a particular
+ * logical processor when an overflow happens, testing has shown that
+ * on kdump kernels (which uses a single cpu), thread1's counter
+ * continues to run and will report an NMI on thread0. Due to the
+ * overflow bug, this leads to a stream of unknown NMIs.
+ *
+ * Solve this by zero'ing out the registers to mimic a reset.
+ */
+ for (i = 0; i < x86_pmu.num_counters; i++) {
+ reg = x86_pmu_config_addr(i);
+ wrmsrl_safe(reg, 0ULL);
+ }
+
return 0;
}